Train-controlling means by light rays



Dec. 18, 1928. 1,695,410

W. BSLR TRAIN' coNTRoLLING MEANS BY LIGHT RAYS W0/ 0/75 e/er y PatentedDec. `18', 1928. I f

UNITED STATES PATENT OFFICE.'

ERUNGS-G. MQB. H., QF BERLIN-TEMPELHOF, GERMANY.

TMm-CONTROLLING MEANS BY LIGHT RAYS.

Original. application filed Februaryl, 1'827, Serial No. 167,759, and in`Germany February 18, 1837.

Divided and this application iiled January 9, 152B. Serial No.245,889.,`

This invention relates'to an a paratus for the automatic controlof-trains y means of light rays and has more particularly for 1ts objectto provide a train control system for automatically stopping alocomotlve of a railroad in case it 1s passing a block signal which hasbeen set against. such passage of the train by a nearbyrail signalstation,

under danger conditions, or for producing only an optical or acousticalarm signal on the locomotive in the event of the enginemansdisregarding a danger stop signal.

The present application is a division of my copending application,Serial No. 167,759, filed Febr. 12t- 1927.

Another object of my invention is to provide means selectivelyresponsive with respect to-diierent points of the track in order toproduce different eiects at such points such as e. g. to'sound an alarmIsignal to remind the -engineman of the approach to a block signal andthen, in the event of the enginemans 'disregardmg this alarm signal toapply the brakes automatically and bring the train to a predeterminedspeed or to complete rest, or for the limitation of the trains speed byautomatically applylng the brakes in successive stages at pre eterminedsuccessive points on the track lying within a given braking 'stretch andthus to cause the train to be brought to rest at a point just to therear of the entrance to the occupied block, irrespective of the speed atwhich the train is travelling and provided only the block remainsoccupied as long as the train is passing this brakin stretch, Whereas inthe event of the blocks ecoming free 'during the trains assing thebraking stretch the actuating devices are to become ineffective avoidingthus an unnecessarybraking'or stopping of the train.

My invention relates to a controlling ratus which makes particular useof t trical properties of 4the well-known appae elecphotoelectric cellsunder various light intensities` such as those consisting essentially ofthe metal selenium. These photo-electric cells have the peculiarcharacteristicof varying their electrical resistance under various lightintensities. Of these properties I make use and I apply them to the imrovements hereinafter more fully set fort presenting for this\object amethod and apparatus which will accomplish the purpose with thecertainty and reliability road service.

Another object of my invention is to provide means for the limitation ofthe trains speed, if a predetermined speed is exceeded over particularparts of the-track such as when passing bridges, curves or likepassages.

The salient principles of my invention consist in the fact that Iprovide in combination a source of light placed on the vehicle orlocomotive, a light sensitive element arranged needed in practical rail-I on the locomotive in proximity to that source of light, and areflecting member or mirror arranged fixedly on the track adjacent to a"blocksignal and serving as an actuating means for causing theestablishment` of a signalling or controlling action 'on the locomotive.This refiecting mirror represents the main feature of my invention andis of a novel and most efficient type tho fulfill the-requirements ofthe system in question. It is a so-called triple mirror and consistsessentially of three reflecting planes two of them being arrangedrectangularly with respect to each other and the third one beingarranged didering Ifrom this rectangular position. Such a triple mirrorhask the property with respect to incoming light rays not to reflect inparallel direction, but to divide andreflect the incoming parallel raysof an aigrette in two symmetric aigrettes of rays. By the use vof atriple mirror as explained I ensure, even with considerable speeds ofthe train that the light sensitive cell on the locomotive is influenceda suiiiciently lon period of time by the light rays radiated y thesource of light on the locomotive to the reflecting mirror on the trackand thrown back again by the same to the locomotive to hit upon thelight sensitive element Whatever their incoming direction may be,

' My invention, as just outlined presents ios ones which are placed atri ht angles with respect to each other or as may call 'it by `'usingtriple mirrors havin different orientation. Thus, each one o saidmirrors has .the property of reflecting incoming light wavesirrespective of their incoming direction at a constant angle, to thisincoming direction, this angle being de endent 'only on the orientationlof each individual mirror. Then, by positioning thesingle lightsensitive cells pertaining to each one of the mirrors in a. properposltion with respect to each other and to the li ht source the effectwill be obtained that eac cell will be struck only by rays coming from adistinct direction which may be adjusted as being that of theorientation of an individual mirror.

According to another feature of my invention I may render the light raysre-selective by varying their intensity periodically or modulating themin accordance with a sine variation such as when employingan A. C.

. supplying an incandescent lamp and by using recelv'mg devicesresponsive to such particular periodicity.

In order that m invention will be more fully understood t e followingdetailed description may be taken, reference bein had to theaccompanying drawings in whiclyi:

Figure l is a schematic view illustratin the salient principles of theworking deta' s of m invention. g

lfigure 2 represents schematically the structure of a triple mirror suchas is used in the apparatus of my invention.

Figure 3 represents schematically the diJI vision of a light ray by atriple mirror such Y as is used in the apparatus of my invention.

Figures 4-6 are illustrative of an arrangement `for successivelyreducing the trains speed ettin selective actions by employerent yorientated mirrors.

Referring more particularly to Figure 1 of the drawing the numeral 1designates .the track, and 2 the locomotive to which is rigidly secureda box 3 containing an incandescent lamp 4 as a-source of light. At thetop of the box 3v is secured a lens 5 projecting a beam of light to atriple mirror 6 secured rigidly on a bracket 7 which vis supported by apole 8 erected at theside of the track adjacent to a blocked section. Aprotecting cover 9 isplaced in front of the mirror to prevent exteriordisturbances from reaching the mirror planes.

At the sides of the box 3 in proximit to the lamp 4 or the lens 5 isplaced a light sensitive element 10. When the locomotive is passin thesignal pole 8, light rays radiated by t e incandescent lamp 4 arereflected vin the same direction as'that in which they reach the mirror6 provided the mirror planes are arranged at right angles with respectto each other, and,thereby hit upon the light sensitive element 10 whichby the variation of its electrical resistance operates a relay of alocal circuit, which relay lntroduces the execution of the actionrequired e. sounds an alarm bell or actuates the braes, in av mannercommonly known in the art and not further described as being without thescope of the invention.

Figure 2 shows schematically the structure of the reflecting mirror asemployed in the arrangement of m invention. 11, 12, 13 are threereflecting planes. If one of the corners-between the planes is notaright angle the incoming beam of a light ray (14) following on one ofthe planes 13 e. g. is reflected Sand divided in two symmetric rays asshown by the numerals 15 and 15" in the drawing.

Thus, referring to Figure 3 where 4 vdesignates the source of light and6"a triplo mirror a ray 14 sent out by the source of lightperpendicularly to the mirror 6 will be reflected into itself in thecase the three mirror'planes are at right angles to each other, but itwill be reflected to points 34 and 35 lying symmetricall l with respectto the source of light in t e case one angle of the planes of the mirroris displaced from its rectangular position.

The dimension of the angle (a) between the incoming and outgoing rays isdetermined bfynthe displacing of the two planes 1.1,

12 e. g. m their rectangular position.

Referring now more particularly to Figures 4 -6`ofthe drawings which areillustrativeof a system for producing selective actions at differentpoints on the track, four reflecting mirrors 16, 17, 18 and 19 arearranged at successive distances along the track,

e. g. of 150 m. from each other. A designates an alarm stop signal and Mthe main ,block signal, their distance apart being 700 m., and it isrequired, in the event of the block being occupied that the train bebrought to rest just to the rear of the block signal irrespective of thespeed with which it is travelling. The mirror 16 is placed at 250 m.distance beyond the alarm sto signal A and 450 m. before the main blocsignal M, the second mirror 17 is placed 300 m., the third mirror 18 isat 150 m. distance from the main iml block signal and the fourth mirror19 is` arranged inclose proximity to the main block signal M. y l Y yAccording to this novel feature of the invention I'employ severalmirrors differently orientated so that the points of light reflected byvthem lie at the circumference of a circle and I place one of thesemirrors at each one of the influencing points 16-19 according to Figure4. In Figure 5 the light points reflected by four of such differentlyorientated mirrors are shown as displaced at an angular distance of 45one from another. Each two symmetrical points 20,l 20', 21, 21', 22,22',

l 23, 2d belong together and are illuminated b one mirror havin a'distinct Iorientation.

he li ht sensitive e ements are arranged at the points 20, 21, 22, 2,3with respect. to 'the light source 4 so that each one will only beinuenced by a beam of light coming from a particular direction on beingilluminated by one of the differently orientated mirrors.

According to Figure the numeral 36 designates a centrifugal speed devicedriven from an axle ofthe locomotive and having an indicating hand 37 ofelectrically conductive material which moves upon a disc having fourcontact segments 24-27 separated by insulating segments; Each of thecontact segments`24-27 is conductively connected to one pole of areceiver (light sensitive element) 28, 29, 30, 31, respectively, theother poles of the receivers being connected to one terminal of a localbattery 38. The other battery terminal is connected in series with thewinding 32 of a relay 33 and with the hand 37 of the centrifugal speeddevice 36. The armature 39of the relay 33 controls an electrical circuitoperating the brakes of the train in a manner'well known in the art. Thecontact segments are so designed that the hand 37 moves on segment 27 asthe train has a speed vless than 25 km. per hour, on segment 26 as longas the speed is between and 25 km.

h. and on segment 25 as long as the speed is between.50 and km. p. h.and on segment 2 4 when the speed exceeps 704 km. p. h. corresponding tothe predetermined maximum speeds attributed to the points 16-19 of thetrack as shown in Figure 4, whereby one of the receivers 28--31 issuccessively included in the circuit of battery 38 according to thespeed existing.A

Byv varying the .length of the contacting .sectors 24-27 an adjustmentfor different categories of trains such as express trains,

goods trains, etc., may be carried out. A further improvement may beincorporated with the arrangement just explained .in that the circuitsclosed by the contacting segments of the contact-disc and consequentlythe relay are rendered ineffective in case the engine driver hasoperated 'the brakes himself.A

Instead of having the hand 37 of the cen# trifugal speed device 36according'to Figure 6 moving'along the contact disc 24- 27 in order torender effective each receiving circuit successively in accordancewithone individual range of speed, the terminals ofthe receivers connectedto the contact disc segments may be connected to the other terminal ofthe battery 38 in series with the winding of the relay 33 and thecentrifugal speed device 36 may turn a covering disc 40 as 'shown byFigure-5 which covers one or more of the receivers 20-23 according tothe speed of the train. In order to have distinct light points the lightrays intendedv to inuence o necreceiver to overla with those intended toact upon the neig iboring receiver collecting lenses may be arranged infront of the mirrors in order to concentrate-the rays into a narrowbeam. I do not desire to limit myself to the particular construction andarran ement of parts shown and described,.but aim in the appended claimsto cover all modifications which are within the spirit and scope of myinvention.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is: 1. In an automatic train control system of the characterdescribed, the combination of electromechanical locomotive control meansof the train brakes including a light-influ-l enced element andactuatable only when said element is influenced by the action of light,

a light source arranged on the locomotive, a light-reflecting memberhaving three reiecting planes positioned in a distinct anglerelationship with respect to each other and adapted to reflect incominglight rays at a and being in its operative position under dangerconditions to reflect li ht rays radiated by said light source on t elocomotive in such a direction as to a'ct upon said light influencedelement.

2. Inan automatic train controll system of the character described, thecombination of` electric-mechanical locomotive control means of thetrain brakes including aplu rality of light-influencedv elementsarranged in predetermined positions with respect to each other and to alight source, said control means being actuatable only when one of saidelements is influenced by the action of light, light refiecting membersbeing fixedly arranged at predetermined distances on the trackadjacentwith respect to a danger section or an occupied block of arailway and being in their operative position under danger conditions,each of these reflecting members having three reflecting planes andadapted to reflect incoming light rays at a constant angle, thisconstant angle being different for each of said reiecting members bypositioning said planes in a proper angle relationship, to reflect lightrays radiated byl said light source on the locomotive in such adirection as to act upon one of said light-influenced elements,

with respect to said ght source, and means for selectively renderingoperative said li ht "electric-mechanical locomotive control means atthereceiving point 20-23 and knot having of the train brakes including aplurality of hght-influenced elements arranged in predepositionedaccordinglyI termined posittion's withq'respec't to each other and to al1 h source,"s`aid control means being actuab e only when one of saidelements g is lnfluenced by the action of light,` light refleetingmembersbeing fixedly arranged at predetermined distances on the trackadjacent to a danger section or an occupied block ,of a.,v railway andbeing in their operative position under danger condition, eachof theserefiecting members having three reiecting pla-nes and adapted toreectfincoming light 'rays at a constant angle, this constant anglebeing different for each of said reflecting 'members by positioning saidplanes in a.` `proper angle relationshlp, to reflect -light raysradiated by said light source on the locomotive in such a direction lasto act upon onev of said light-inluenced elements sitioned accordinglywith respect tosaid ight 4source, and acentrifugal speed device ada. t`

WOLFGANG BSELER. i

